If the first free practice session of the Korean Grand Prix is an indicator, then Red Bull and Mercedes look likely to be slugging it out around the venue in Yeongam for top honours this weekend as Lewis Hamilton set the early pace by the slightest margin over Sebastian Vettel and Mark Webber.

With a few minutes left in the session Kimi Raikkonen made a rare mistake and crashed into the barriers at the Turn 17 complex, seriously denting all four corners of his Lotus. The Finn, who nursed a back injury throughout the Singapore GP weekend, walked back to the pits apparently unaffected by the shunt.

At the sharp end Hamilton and teammate Nico Rosberg swapped places at the top of the timing screens. But at around the hour mark the Briton posted a time of 1.39.630 which was good enough for top spot, with Rosberg fourth fastest albeit 0.487 of a second down on his Mercedes teammate.

Sebastian Vettel was second fastest in FP1

World Championship leader, and winner at the venue for the past two years, Vettel came closest to dislodging the Silver Arrows from top spot, but in the end fell short by a mere 0.037 with Webber a mere 0.149 of a second slower than his teammate.

Best of the rest, and somewhat surprisingly, was Jenson Button in the McLaren with the fifth fastest time and also racking up the most laps in the ninety minute session. Sergio Perez in the sister car was ninth on the timing sheets.

Fernando Alonso was sixth fastest in the Ferrari, 0.744 off Hamilton’s best with teammate Felipe Massa tenth best, but half a second down on the Spaniard.

Kimi Raikkonen’s damaged Lotus is returned to the pits

Up next were the Lotus pair in the long wheelbase version of the E21, which had been on ice since Monza where Lotus first ran it. For Korea at least, the team has reverted to the original, shorter model. Romain Grosjean was seventh fastest. Before his crash Raikkonen was ninth, where he remained until the chequered flag dropped to end the session.

There were a number of incidents during the session not helped by a dusty track and a very green surface, which turned Turn 10 into a tricky section which caught out several drivers including Hamilton.

Rodolfo Gonzalez, on duty for Marussia in the car of Jules Bianchi, spun and smacked the wall. He made it back to the pits where the team repaired the MR02 and the Venezuelan was back out on track in less than half an hour. He ended the session slowest of all.

James Calado was on duty for Force India in place of Paul di Resta. (GP247)

Subbed by AJN.

Rodolfo Gonzalez returns to the pits after crashing the Marussia in FP1